AB0971 EFFECTIVENESS OF IGURATIMOD IN THE TREATMENT OF AXIAL SPONDYLOARTHRITIS-REAL WORLD DATA FROM CHINA
Authors: Y. Li, Z. Zhao, L. Hu, Z. Hu, J. Jin, J. Zhang, J. Zhu, F. Huang
Journal: Annals of the Rheumatic Diseases (2023)

<h3>Background</h3> Axial spondyloarthritis (ax-SpA) is a group of chronic auto-inflammatory diseases. Tumor necrosis factor-alpha (TNF-α) and interleukin-17 (IL-17) were demonstrated to play an irreplaceable role in the pathogenesis of ax-SpA. Iguratimod is a newly-developed small molecular anti-rheumatic drug, which can inhibit the effects of prostaglandin E2, TNF-α and IL-17 <sup>[1]</sup>. The efficacy and safety of Iguratimod in the treatment of rheumatoid arthritis (RA) have been fully studied and approved to the treatment of active RA in China and Japan <sup>[2]</sup>. Iguratimod had been reported to be effective in the treatment of ax-SpA <sup>[3]</sup>, despite those studies were limited and of small-example size. <h3>Objectives</h3> In consideration of the efficacy of Iguratimod in the treatment of RA and the overlap of disease pathogenesis between RA and SpA, Iguratimod was implied to be of potential efficacy on ax-SpA. This study was aimed to demonstrated the efficacy and safety of Iguratimod on ax-SpA in the real word from China. <h3>Methods</h3> 1993 patients with ax-SpA who visited the outpatient rheumatology clinics in the First Medical Center of Chinese PLA General Hospital between April 2016 to June 2022, were collected and screened. Patients treated with NSAIDs only, combined with sulfasalazine (SSZ) or Iguratimod for over 6 months were admitted into analysis. Those three groups of patients were also matched by propensity score on a ratio of 1:1:1, by age, gender and ASDAS at baseline. Multilevel models for repeated measurement data were conducted to compare the differences of ASDAS, back pain, ESR and CRP level between the three groups of patients during the 18 months follow-ups. <h3>Results</h3> 302 patients with ax-SpA were included in the real-world study and they were followed at a mean 6-month interval for 3 times (median follow-up 17.55 months, interquartile range 16-20 months). 161, 96 and 45 patients fell into the NSAIDs only, NSAIDs combined with SSZ or Iguratimod group. At the baseline, those three groups of patients had significantly different back pain scores, PGA, PhGA, ASDAS, ESR and CRP level (P&lt;0.05). At the end of follow-up, patients treated with Iguratimod had significant improvement on the primary endpoint (ASDAS, 1.51±0.67 vs. 2.07±0.90, P&lt;0.001) and secondary endpoint (BASDAI, 1.48±0.94 vs. 1.98±1.49, <i>P</i>=0.027; Back pain scores, 1.91±1.14 vs. 2.64±1.69, <i>P</i>=0.007; PGA, 2.07±1.39 vs. 2.78±1.57, <i>P</i>=0.015; PhGA, 2.20±1.16 vs. 2.96±1.45, <i>P</i>=0.003; CRP, 3.47 mg/L vs. 5.20 mg/L, <i>P</i>=0.017) than that at the baseline. Patients treated with NSAIDs and Iguratimod had higher clinically important improvement rate that that treated with NSAIDs combined with SSZ (26.66% vs. 8.33%, <i>P</i>=0.008)or NSAIDs only (26.66% vs. 8.70%, <i>P</i>=0.004). 135 patients were matched by propensity score matching (45 patients on each group) and after adjusting for potential confounding factors, patients treated with NSAIDs and Iguratimod had greater improvement on ASDAS than that on patients treated with NSAIDs combined with SSZ (β&lt;0.001, 95% CI: 0.000 ~ 0.001, <i>P</i>=0.043) or NSAIDs only (β&lt;0.001, 95% CI: 0.000 ~ 0.001, <i>P</i>=0.033). <h3>Conclusion</h3> Iguratimod had significant add-on effect on the decrease of disease activity and alleviation of back pain than monotherapy of NSAIDs or NSAIDs combined with SSZ. Iguratimod is effective and well-tolerated during the treatment and thus could be a new pharmaceutical option for ax-SpA patients. <h3>References</h3> [1]Li J, Bao J, Zeng J, et al. Iguratimod: a valuable remedy from the Asia Pacific region for ameliorating autoimmune diseases and protecting bone physiology[J]. Bone Res, 2019,7:27. [2]Suto T, Yonemoto Y, Okamura K, et al. The three-year efficacy of iguratimod in clinical daily practice in patients with rheumatoid arthritis[J]. Mod Rheumatol, 2019,29(5):775-781. [3]Li Y, Li K, Zhao Z, et al. Randomised, Double-Blind, Placebo-Controlled Study of Iguratimod in the Treatment of Active Spondyloarthritis[J]. Front Med (Lausanne), 2021,8:678864. <h3>Acknowledgements:</h3> NIL. <h3>Disclosure of Interests</h3> None Declared.